Hi, I've got a 1997 1.8 ADR 20v A4 Avant,

When I got the car (2nd hand), the coolant was empty. I topped it up with just water for the drive home and then added some coolant when I got back. After a week it was all gone again. I topped it up with the correct coolant / water mix again and it has been fine since (2-3 months and lots of milage).

However, in all of this time, neither the air con or the heaters have been working. I've checked out as many forum posts as humably possible on this matter and as far as I can gather, the flap valves are fine, the pipes through the firewall are fine (getting hot), the air con switch and compressor both activate perfectly. There is an increase in temp when increasing the temp controller from hot to cold. (not enough though).

I noticed on one post, that you could bleed the coolant throught the coolant bleeder hole in the pipes leading to the heater core. I opened the clip, slid the pipe back so that the hole was open, lifted the coolant resevoir and nothing happened. No coolant at all (for over 5mins) with engine on and fans on high. So I pulled the pipe off the "nipple" fully and there was only a dribble of coolant that dripped out of the pipe.

Do I have a blockage? (note no over heating, and thermostat ok).

A mechanic stated that it could either be a coolant blockage (but why would the pipes still be getting hot), a blockage in the heater core (suggested renewal ) or a dodgy flap valve.
I do remember squeezing the firewall pipes a while back and noticed they were crunchy on the inside!!?!

Please help!

Also, on my model (manual transmission) should I have any kind of readout on the dash board on the two thin sections below the fuel light boxes as mine are blank. I've noticed on images that they often contain outside temp and gear selection. But I assume this is only on Automatic models.

Thank You

Martin

 

you need to bleed system again.

Don't need to have car running.

open the valve again on the heater core pipe.

remove the bolts from the resevoir. Hold it up in the air as high as you can.

Have someone else pour coolant in while you hold it. Continue filling until coolant begins to come out of hole on heater core intake.

Then close hose up on the pipe. Put resevoir back in place, and fill to proper level. Run engine, make sure level stays right.

Then try the heater.

 

Hi,

As the reservoir is still at the max line even when lifted, will I be able to add more coolant, as surely it will just over flow?

Others have mentioned flushing the entire system to try and remove any blockages first. I've read up on this in the Haynes manual and it suggests removing the thermostat first. Is this necessary, and if so where will I be able to find a replacement rubber seal.

Thanks

Martin

 

When you mix different types of antifreeze, you can end up with
a jello like consistency. I'd fush the system, then add either G-12
or universal yellow with distilled water.

 

definitely refill with g12, and water 50/50.

 

Hi,
I flushed the entire system with the garden hose and then refilled with coolant and bled it properly. I now have heat. It's not quite as hot as it should be but its much warmer all the way to work now.

Cheers Guys

Martin

 

you should have flushed it again. like stated above if you have the jello stuff from combining coolants than you will need to flush it a lot more to get that out. congrats on the heat! you're going to need it with winter and all. mine blasts me out of the car. that plus the seat heater and i'm sweating by the time i get to work!

 

You didn't run straight coolant did you?????

Thats a no-no, and could be why your heat is not warm. Usually its supposed to be a 50-50 mix, or somewhere close to that like 60-40.

Straight coolant will not be efficient, and will shorten the life of the cooling system.

 

Don't worry guys, I mixed the coolant first according to Haynes so that wont be and issue and in regards to the jello stuff. I flushed it and flushed it again before i filled up. THhre was nothing but pure water left in the pipes.

Thanks for the concern though

Martin

 

Good job.

just checking.....